Supervisory Uniqueness for Operating Mode Systems

Multi-model approaches to Discrete-Event-Systems (DES) are ideally suited to implementing operating mode management and inter-mode phase alternation (switching) policy. The resulting major problem involves respecting full system evolution tracking (both plant and specifications) when inter-mode switching is evoked. In other words, after jumping from a mode to another, the newly activated mode must be directed to a state (its starting state) corresponding to the full system evolution state.The aim is therefore to determine the possible starting states of each operating mode. This study develops the underlying notion that, whilst the tracking mechanism is required at plant level, it is extended to supervision level in the sense that specification interpretation remains unchanged in relation to the various starting states.